Live shaft idler pulley



March 9, 1954 Filed Aug. 31, 1951 C. C. MOORE LIVE SHAFT IDLER PULLEY 2 Sheets-Sheet l INVENTOR.

aw M8 m March 9, 1954 c. c. MOORE 2,671,348

LIVE SHAFT IDLER PULLEY Filed Aug. 51, 1951 2 Sheets-Sheet 2 HOT ZONE 29 I INVENTOR. awza m V Patented Mar. 9, 1954 LIVE SHAFT IDLER PULLEY Chester Charles Moore, Aurora, 11]., assignor to Stephens-Adamson Mfg. 00., a corporation of Illinois Application August 31, 1951, Serial No. 244,542

1 Claim.

This invention relates to the manufacture of live shaft idler pulleys for supporting belt conveyors and the like.

Heretofore, such pulleys have been made by fabricating spaced, disk-like end pieces to a tubular rim and a length of shafting, which involved many operations, such as:

1. Cutting the rim from steel tubing;

2. Counter-boring it at each end;

3. Making the disk-like ends by stamping or casting;

4. Cutting the shafting; and

5. Assembling the several parts and making them fast by welding, crimping, etc.

The commercial tubing does not run very uniform in diameter or circular section. Much metal strength is lost in counter-boring and fitting; and uniformly good welding or other fastening is diflicult to get in production.

The principal object of this invention is to make live shaft pulleys in one piece with accurate and appropriate distribution of metal in all parts.

Generally speaking, this is accomplished by cutting a suitable length of steel tubing and spinning the end portions to form the disk-like webs integral with both the rim and projecting trunnions that serve as a shaft.

Further objects and advantages of the invention will appear as the disclosure proceeds and the description is read in connection with the accompanying drawings, in which Fig. 1 is a diagram of the tool for doing the spinning;

Fig. 2 is a part elevation and part longitudinal section of the pulley;

Fig. 3 is an end view of the same;

Fig. 4 is a part elevation and part section showing the tube which forms the starting blank and a number of positions of the end portions of the metal during the spinning operation;

Fig. 5 is a similar view indicating different positions of the metal as the trunnion is formed on the end; and

Fig. 6 is a section showing a finished end piece and trunnion of the pulley.

In Fig. 2, It] indicates, generally, the idler pulley composed of a rim portion I I, dished end portions l2, and trunnions 13, all in one integral piece of steel.

According to this invention, that idler pulley is made from a blank M of steel tubing cut to suitable length to provide the necessary metal for forming the end pieces and the trunnions as well as to provide the supporting rim of the pulley.

In Fig. 4, the numeral 1 indicates the position of the end metal to be worked at the outset of the operation. 2, 3, and 4 indicate successive positions through which the metal is worked; and 5 indicates the form that may be taken as the end of the tube is completely closed.

Also, in Fig. 4, 6 indicates one position of the metal during the start of the trunnion, and I in Fig. 5 indicates the full trunnion drawn out on the center of the end portion of the blank.

In Fig. 5, 8 indicates one position as the trunnion is being spun back into the pulley; and 9 in Fig. 6 indicates the final position.

Fig. 1 indicates, in diagram, a machine tool for performing the operations described, in which 15 indicates the side rails of a lathe or lathe-like machine having a turret carriage I6 mounted thereon equipped with a tool turret II having a tool post [8 for a spinning tool I 9.

The carriage I6 is provided with a cross-feed table or carriage 20 on which the turret I1 is actually mounted.

The carriages l6 and 20 and the turret I! are shown as being adjusted to position by hydraulic cylinders 2!, 22, and 23 controlled by valves 24, 25, and 26.

It will be clear from the arrangement that the tool I9 can be moved into any suitable position for contact with the work, and then shifted as it is desired to make the metal flow.

The machine tool has a head 2'! equipped with a magnetic chuck 28 to receive and hold the blank I4.

In operation, the blank having been pre-heated for a suitable length at the end indicated in Fig. 4 by the hot zone 29 in any suitable manner, as by a torch 30, the tool I9 is brought into position to spin the metal substantially as illustrated in Figs. 4-6 and described above. Preliminary heating to dull red would ordinarily be sufficient, and the friction of the spinning tool will heat the steel to melting while the metal is made to flow as described and the trunnion is puddled by the tool.

All the metal in the finished pulley is contained in the original blank [4 of steel tubing, and is finally concentrated in the finished end, except for a slight machining operation on the trunnion. By the procedure indicated, the weight and thickness of the disk-like end portion of the trunnion can be determined, and the thickness and distribution of the metal made to suit the strength required in the service to which the idler is to be put.

The shape and distribution illustrated in the drawing are substantially such as will be found satisfactory. There is no scrap.

I claim:

A one-piece live shaft idler pulley for a belt conveyor or the like including a tubular sheet metal rim of relatively large radius and long axial length, a solid end disk integral with each end portion of the rim connected with the adj acent end portion by a radially inwardly rounded edge of relatively short radius curving axially inwardly through more than ninety degreesof arc and provided adjacent to its axis with a solid thickened zone having an axially outwardly curved outer surface and an axially in-' wardly bulged inner surface, and a solid trunnion projecting axially outwardly from said thickened zone, the entire pulley having been formed by spinning the end portions of a straight length of tubing into said end disks and trunnions and thereby causing the inner surfaces of the respective end portions of the tubing to flow into mutual engagement to form the solid thickened zones and trunnions at said end portions.

CHESTER CHARLES MOORE. 

